1. Field of the Invention
The present invention relates to an image pickup apparatus that performs image processing with respect to an image pickup device that picks up an image of an object.
2. Description of the Related Art
Image pickup devices that pick up an image of an object have been widely used in recent years in image pickup apparatuses such as endoscope apparatuses.
Recently, the number of pixels of image pickup devices has been increasing and miniaturization of image pickup devices has been also progressing, and it is almost impossible to manufacture an image pickup device without pixels that have a defect or pixels that generate noise.
Consequently, many kinds of technology have been proposed that employ image processing to correct defective pixels that generate pixel signals that are different to normal pixels of an image pickup device and also to correct fixed pattern noise.
For example, Japanese Patent Application Laid-Open Publication No. 2003-116060 as a first conventional example discloses technology in which a defective pixel correction portion includes therein a defect position recording ROM that records positional information of a defective pixel that is obtained by performing a prior inspection, and determines a direction in which there is a high correlation based on peripheral pixels of the defective pixel that can be identified based on the defect position recording ROM, and calculates a correction value of the defective pixel using peripheral pixels that belong in the direction in question.
Further, in paragraph [0016] of Japanese Patent Application Laid-Open Publication No. 10-042201 as a second conventional example it is described that “Interpolation is utilized with respect to image information on a same line as a defective pixel using mainly video information on a preceding line and video information on a succeeding line excluding the data of the defective pixel and of a pixel before and after the defective pixel. Since correction is performed using video information on the preceding line and video information on the succeeding line, interpolation is possible with respect to not only the defective pixel but also for signals before and after the defective pixel.”